Method of cooling exhaust gas turbo-blowers for diesel engines



A. MEYER April 12,1932'.

METHOD OF COOLING EXHAUST GAS TURBO BLOWERS FOR DIESEL ENGINES FiledDeo. 27, 1927 PAPl'. 12,. A1932 UNITED STATES PATENT. OFFICEOI'IUSNAGHT, NEAR. ZURICH,

c T BROWN, POVERI AND CIE., I' BADEN, SWITZERLAND 2 Alvi:

,n .ASSIGNOB T0 AKTIEN- mHUD 0l' GDOLING EXHAUST TURBO-BLOWEBS FOBlIDIIIEISEJ: ENGINES Application Iles! December 27, 1927, Serial No.248,840, 4and in Switzerland December 30, 1928.

For driving the charging and scavenging air blowers of internalcombustion engines gas turbines are frequently employed, which aredriven with the exhaust gases from the 5 Diesel engine. 'Ihese exhaustgases have temperatures according to the load, which may exceed 500. Forthis reason it is necessary to cool the bearings, glands, shafts and,

such water is not availab e, as the Diesel engines are, as is welllmown,used more particularly in regions .which are deficient in water supply.On locomotives as well, there may be a lack of Water. Hence, a further 35 advantage is provided by the proposal to use air instead of water forcooling purposes,

thatis, air conveyed by the blower, which has however been obtained fromthe delivery side and therefore entails a loss in output.

A particularly advanta eous manner of cooling is provided accordmg tothe invention, by using the waste air from the balancing piston of theblower, as this air is in any case lost.

The invention will now be described by way of example with reference tothe accompanying drawings, wherein: Y

Figure 1 represents a sectional view of a gas turbine blower combinationembodying 4 the invention.

Figure2 is a sectionalview of a similar combination modified 'so thatthe waste air from the balancing piston enters the gas turbine casingdirectly along the shaft.

Aceordingto Figure 1 the bearing avof the turbine b is cooled by airwhich flows gdm the balanc' piston o `of v the blower d.

This wasteair om the balancing piston may also be caused to enter theeasing ofthe 5 gas turbine directly along the shaft, ,so that Away ofexample in Fi no glands are required at this point for the blower andthe gas turbine, as is shown by gure 2. Around the shaft 3 from theturbine wheel 2 to the blower casing 4 Va closed space is formed so thatthe coohng air can -no longer esca e into the open, as heretofore, butpasses om this space along` the shaft into the casing 1 of the gasturblne, leaving the latter along with the waste ygases of the turbine,through the exhaust pipe 7. By this means notonly is the cooled part ofthe shaft made longer and the heatedpart shorter, but, by mixing, thetemperaturel in the casing of the turbine is also reduced, thus causingthe shaft to be further cooled. This also does away with one of theglands and prevents the undesirable escape of the hot gases out of the"gas turbine along the shaft. For this urpose it is only necessary to'maintain in t e cooling space a res'- sure slightly above that of theatmosp ere, which is somewhat greater than the exhaust pressure of thegas turbine which normally exhausts into the open. For increasing thecooling action and reducing the quantity of air required `for cooling,the shaft may, as shown, be provided with ribs 8 between which opposingribs of the casing en age for lengthening the path` of the air anincreasing the velocity of the air, forthe purpose of increas ingthetransmission of heat.

For this cooling, just as in the example shown in Figure 1, the wasteair from the balancing piston 6 of the blower is used. In combinationshaving two bearin such as that shown in Figure 2, this enab es themachine to be still further shortened, as the blower and the gas turbinemay be made integral with one another, both the gland of the blower andthat of the gas turbinebeing done away with and the air which leaks pastthe balancing piston being capableofv flowing directly along the shaftinto the casing of the gas turbine.

Having now described my invention, what I claim' as new and desire tosecure by Letters Patent is 1. A methodlof Ycooling exhaust gasturboblowers furnished with a balancing piston which consists inconveying waste air from 1 the said balancing pist-,on to th said gas,turf` f bine as and for the purpose described.

2. Means for cooling parts of a gas turbol blower including' a singleshaft carrying both gas turbine and blower, a balancin pisto on saidshaft associated with said b ower and a duct conduct' waste air from thelow pressure side of said alancing piston past the Y parts to be cooled.

3. Means for'cooling parts of a gas turbo- I c blower as claimed in aim2 includin a single casing housing both the gas turbine an the blowerwith its balancin piston, the said duct bein formed between t e shaftand the casing an extendin fromv the balancing piston of the blower to te gas turbine.

4. Means for cooling parts of a gas turboblower as claimed in claim 2including a single casing housin both the gas turbine andthe blower withits balancin piston, the said duct bein formed between t e shaft and thecasing an extending from the balancing piston of the blower to the gasturbine, outwardly projecting rings on the shaft coacting with inward yprojecting rings on the casing to form la labyrinthine duct and thusincrease the effective length of the waste air path through the saidduct.

In testimony whereof I have signed my name to this specification. A

ADOLF MEYER.

